State of Art: The Fire Resistance of RC Members Strengthened with CFRP Laminates

Document Type : Original Article


Department of Civil Engineering, Faculty of Science and Technology, University of Coimbra, Coimbra, Portugal


The available current research on mechanical behavior of RC structural members strengthened with CFRP material resulting from fire is presented and technically discussed in this paper. This includes design reviews, methods of application and techniques of reinforcing RC members with CFRP. Besides, the review includes the latest developed experimental, numerical, methods and formulation studies. Moreover, most of the studies agreed that there is a need to conduct more parametric numerical analysis in the field for improvement the global thermal response and flexural strength of the RC members strengthened with FRP. Based on the missing research, this review paper propose and suggest a set of very innovative design strategies and methods of application to improve the fire response of FRP laminates in case of fire, such as, (1) a combination design reinforcement technique on RC structural beam members with a combined mechanically anchored 3NSM extruded FRP design, (2) RC structural members external bonded with zigzag shaped FRP strips at the bottom and side soffits, (3) installing steel wire mesh, textile wire mesh and carbon tissues as a reinforcement material in the fire protection layer, (4) testing the fire response of using π-anchor and FRP anchor devices and new shaped memory alloy material in RC structural members strengthened with FRP, (5) u-shaped steel anchorage plate installed in the mid-span of the RC FRP beam, (6) suggesting installing L-shaped steel plate as a form of anchorage tool to support the bottom and the vertical soffits of the extruded FRP and (7) fire response of RC beams strengthened with FRP laminates using 3 different pre-fabricated types of extruded FRP laminates. The aim of this paper is to contribute for a more effective research on this field, leading to a future wide use of this technique in safer RC structures to fire events.


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